Chauvin Arnoux C.A 6521 User manual

1
FRANÇAIS
ENGLISH
DEUTSCH
ITALIANO
ESPANOL
C.A6521
C.A6523
C.A6525
■MEGOHMMETRES
■MEGOHMMETERS
■MEGOHMMETER
■MEGAOHMMETRI
■MEGAÓHMETRO
Notice de fonctionnement
User's manual
Bedienungsanleitung
Libretto d’Istruzioni
Manual de Instrucciones

22
Meaning of the symbol
Warning ! Please refer to the User’s Manual before using
the instrument.
In this User’s Manual, the instructions preceded by the above
symbol, should they not be carried out as shown, can result
in a physical accident or dammage the instrument and the
installations.
Meaning of the symbol
This device is protected by a double insulation or by a
reinforced insulation.Nolinkingisrequired fromthe protection
earth terminal to ensure the electrical security.
Meaning of the symbol
Warning ! Risk of electric shock.
The voltage of the parts marked with this symbol may be
dangerous. For safety reasons, this symbol will light up on
the LCD screen as soon as a voltage is generated.
Thank you for purchasing a C.A 6521, C.A 6523 or C.A 6525
insulation tester.
To get the best service from this instrument :
■read this user’s manual carefully
■respect the safety precautions detailed
PRECAUTIONS FOR USE
■Comply with the conditions for use : temperature, humidity,
altitude, degree of pollution and place of use
■This instrument can be used on category II installations for
voltages which do not exceed 300 V in relation to the earth.
The equipment classified in category II is energy-consuming
equipment, receiving its power supply from the fixed
installation (cf. IEC 664-1, 1992 edition).
■Do not perform any insulation or resistance measurements
when the presence of a voltage is indicated.
■Use connection accessories that comply with the applicable
IEC safety standards, with a minimum voltage and voltage
surge category at least equal to those that you use for your
measurements.
■Respect the value and type of the fuse to avoid damaging
the instrument and cancelling the warranty.
■Set the switch to OFF when the instrument is not in use.
■Check that none of the terminals is connected and that the
switch is set to OFF before opening the instrument.
English

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CONTENTS
1. PRESENTATION
1.1. General Presentation ...................................................25
1.1.1. The Megohmmeter.................................................25
1.1.2 Accessories............................................................25
2. DESCRIPTION
2.1. Unit................................................................................26
2.1.1. C.A 6521 ................................................................26
2.1.2. C.A 6523 ................................................................26
2.1.3. C.A 6525 ................................................................26
2.2. Display ..........................................................................26
2.2.1. Symbols .................................................................26
2.2.2. Bargraph.................................................................27
2.2.3. Digital display .........................................................27
2.3. Control keyboard ..........................................................27
2.3.1. Yellow key...............................................................27
2.3.2. ALARM key (C.A 6523 and C.A 6525) ..................27
2.3.3. Key (C.A 6523 and C.A 6525) ...........................27
2.3.4. Key (C.A 6523 and C.A 6525) ...........................28
2.3.5. Key (C.A 6523 and C.A 6525) .........................28
2.3.6. TIMER key (C.A 6525) ...........................................28
3. MEASUREMENT FUNCTIONS
3.1. Insulation ......................................................................28
3.1.1. Safety checking ......................................................28
3.1.2. Insulation measurement ........................................29
3.2. Continuity......................................................................29
3.3 Resistance (C.A 6523 and C.A 6525) ..........................30
4. SPECIAL FUNCTIONS
4.1. Start/stop ......................................................................30
4.2. Automatic shutdown .....................................................30
4.2.1. Deactivation of automatic shutdown function ........31
(C.A 6523 and C.A 6525).......................................31
4.3. Power supply autotest ..................................................31
4.4. Buzzer...........................................................................31
4.4.1. The different audible signals ..................................31
4.4.2. Deactivation of the buzzer .....................................32
4.5. Alarm thresholds (C.A 6523 and C.A 6525).................32
4.5.1. Programming of the alarm thresholds ...................32
4.5.2. Activation/deactivation of the alarm thresholds.....32
4.5.3. Triggering of the alarm ...........................................33
4.6 Compensation of measuring leads ..............................33
(C.A 6523 and C.A 6525) .............................................33
4.7. Timer (C.A 6525) ..........................................................34

5. USE
5.1. Insulation testing ..........................................................35
5.2. Continuity measurements.............................................35
5.3. Resistance measurements (C.A 6523 and C.A 6525)......36
6. CHARACTERISTICS
6.1. Reference conditions....................................................36
6.2. Characteristics per function..........................................36
6.2.1. Voltage ...................................................................36
6.2.2. Insulation ................................................................36
6.2.3. Continuity ...............................................................37
6.2.4. Resistance (C.A 6523 and C.A 6525)....................37
6.2.5. Timer (C.A 6525)....................................................38
6.3. Power supply ................................................................38
6.4. Climatic conditions .......................................................38
6.5. Variations in nominal field of use .................................38
6.6. Limits ............................................................................39
6.7. Construction specifications ..........................................39
6.8. Compliance with international norms ...........................39
6.8.1. Electromagnetic compatibility : EC compliance ....39
6.8.2. Mechanical protection ............................................39
7. MAINTENANCE
7.1. Upkeep..........................................................................39
7.1.1. Replacing the batteries ..........................................39
7.1.2. Replacing the fuse .................................................40
7.1.3. Cleaning .................................................................40
7.1.4. Storage ...................................................................40
7.1.5. Calibration ..............................................................40
7.2. Maintenance .................................................................40
8. WARRANTY ...................................................... 41
9. TO ORDER ........................................................ 41
10. APPENDIX
10.1. Front views ................................................................ 102
CA. 6521 .................................................................... 102
C.A 6523 .................................................................... 103
C.A 6525 .................................................................... 104
10.2. Examples of applications .......................................... 105
10.2.1. Insulation measurements on installations .......... 105
10.2.2. Insulation measurements on cables ................... 106
10.2.3. Insulation measurements on motors .................. 107
10.3 Accessories ............................................................... 108
10.3.1. Shoulder bag ....................................................... 108
10.3.2. Use of the shoulder bag...................................... 108
10.3.3. Remote control probe ......................................... 109

1.PRESENTATION
Terminology
The term “continuity” will be used to mean a resistance
measurement performed with a current of at least 200 mA (with
the measured resistance lower than 20 Ω) in accordance with
the IEC 61557 norm, to distinguish it from a resistance
measurement(C.A 6523and C.A6525)performedwith acurrent
that is not predefined.
1.1. General Presentation
1.1.1. The Megohmmeter
These portable instruments function with batteries or a
rechargeable battery.They can be used to check the insulation,
continuity and voltages and to measure resistances.They help
to ensure the safety of electrical installations. The acquisition,
processing and display of the measurements are managed by
a microprocessor,
They offer a large number of advantages such as automatic
detection of a dangerous voltage on the MΩcalibre terminals
(with blocking of any insulation testing ifV > 25V), protection of
the instrument against external voltage surges, improved
operatorsafetythroughautomaticdischargingof thehighvoltage
fromtheequipment tested,automatic shutdown oftheinstrument
to optimize the battery charge life, a large LCD display with a
wide range of indicators that is very easy to read, etc. And,
depending on the model, backlighting of the LCD (C.A 6523
and C.A 6525), programming of the thresholds (C.A 6523 and
C.A 6525), the possibility of compensated leads for continuity
(C.A 6523 and C.A 6525), and display of the duration of the
measurement (C.A 6525).
1.1.2 Accessories
■Shoulder bag (delivered with standard instrument, see § 10)
When placed in the shoulder bag, the instrument can either be
carried on the shoulder to transport it or around the neck for
use. This leaves the users’ hands free to perform the
measurements. Since the instrument is perpendicular to the
chest, it is easy to read.
At the bottom of the shoulder bag, underneath the instrument,
there is a pocket for the leads, the touch prod, the crocodile
clamp and the remote control probe.
■■
■■
■Remote control probe (option, see § 10)
This probe is used with the C.A 6523 and C.A 6525.These are
equipped with the special connector required to connect it to
the instrument.
It can be used for all the measurements, including activation of
insulationtesting, using theyellow buttonwhich worksin exactly
the same way as the button on the instrument.

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A pushbutton on the back of the probe allows you to light the
measuring point (lighting of approx. 500 lux). This function is
veryuseful, since insulation testing is performed on installations
with the power off!
2. DESCRIPTION
2.1. Unit
See the diagrams of the instruments in § 10 (appendix at the
end of this user’s manual)
2.1.1. C.A 6521
➀2 safety terminals, Ø 4 mm (marked “ + “ and “ - “)
➁5-way switch: OFF, MΩ- 250 V, MΩ- 500 V,
20 Ω+, 20 Ω-
➂Yellow key (to activate insulation measurement)
➃Liquid crystal display
➄Battery compartment + stand (not shown in the drawing)
2.1.2. C.A 6523
➀2 safety terminals, Ø 4 mm (marked “ + “ and “ - “). Next to
the “ – “ terminal, there are two additional contacts for
connecting the remote control probe (3-point connector).
➁6-way switch :OFF, MΩ- 500V, MΩ- 1000V, 400 kΩ, 20 Ω+,
20 Ω-
➂Yellow keys (to activate insulation measurement), ALARM,
, and etc.
➃Backlit liquid crystal display
➄Battery compartment + stand (not shown in the drawing)
2.1.3. C.A 6525
➀2 safety terminals, Ø 4 mm (marked “ + “ and “ - “). Next to
the “ – “ terminal, there are two additional contacts for
connecting the remote control probe (3-point connector).
➁7-way switch : OFF, MΩ- 250 V, MΩ- 500 V,
MΩ-1000 V, 400 kΩ, 20 Ω+, 20 Ω-
➂Yellow keys (to activate insulation measurement), ALARM,
, , and TIMER.
➃Backlit liquid crystal display
➄Battery compartment + stand (not shown in the drawing)
2.2. Display
2.2.1. Symbols
Timer active (in TIMER mode)
ALARM Thresholdactiveorthreshold programmingin progress
>Upper threshold
<Lower threshold

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Dangerous voltage generated
!
See the user’s manual
> 25 V Voltage > 25 V
W0
Compensated leads
Buzzer active
P
Constant operation (no automatic shutdown)
Batteries flat
W0
Fixed and Flashing :
incorrect compensation of the leads
2.2.2. Bargraph
Insulation > 2 GΩ
Insulation < 50 kΩ
2.2.3. Digital display
BAT Batteries low – must be changed
OL Range exceeded
- - - Insulation < 50 kΩat 250 V, < 100 kΩat 500 V
or < 200 kΩat 1000 V
2.3. Control keyboard
2.3.1. Yellow key
When this yellow key is pressed, a high voltage is generated for
insulation testing. However, if a voltage greater than 25 V has
been detected, no insulation testing is allowed and the key
becomes inactive.
In all cases, this key is only active for as long as it is pressed,
except in the TIMER mode specific to the C.A 6525 (first press
= activation, second press = deactivation).
2.3.2. ALARM key (C.A 6523 and C.A 6525)
The ALARM key can be used to activate/deactivate the alarm
thresholds during insulation, resistance and continuity
measurements.
When associated with the and keys, it can be used to
program the values of these thresholds.
2.3.3. Key (C.A 6523 and C.A 6525)
When programming the alarm thresholds, the key makes
the following elements flash in succession :
■the measurement unit digit (if there is one),
■the thousands digit,
■the hundreds digit,
■the tens digit,
■the units digit,
■the decimal separators,
■the type of threshold (upper or lower),
■and it then returns to the measurement units.

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2.3.4. Key (C.A 6523 and C.A 6525)
When programming the alarm thresholds, the key can be
used to scroll through the possible values, which flash, and then
loop back to the beginning :
■MΩor GΩfor insulation, kΩor Ωfor resistance, for the
measurement units,
■1,2, 3 or _ for the thousands digit,
■0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 for the hundreds, tens and units,
■“-.- - -” or“- -.- -” or“- - -.-”or “- - - -”for the decimal separator,
■> or < for the upper or lower threshold.
2.3.5. Key (C.A 6523 and C.A 6525)
When the key is pressed, the backlighting of the display comes
on.It will be turned off automatically one minute later.When it is
lit, you can turn the backlighting off by pressing this key again.
2.3.6. TIMER key (C.A 6525)
This key can be used to activate/deactivate timed insulation
measurement.
3. MEASUREMENT FUNCTIONS
3.1. Insulation
The insulation measurements correspond to the MΩpositions
of the switch.
3.1.1. Safety checking
The insulation measurement shall be performed when the
equipment is idle. The apparatus nevertheless automatically
detects and indicates the presence of a voltage on its terminals.
If the voltage present is less than 25 V, the insulation can be
tested, but the lower the test voltage (250 V, 500 V or 1000 V)
the greater the possibility of error.
If the voltage is greater than 25 V, “ > 25 V “ is displayed.
Pressingtheyellowkeydoes nottrigger insulationmeasurement,
but causes a series of buzzes (buzz, buzz, buzz, ...) and makes
the symbol flash until the yellow key is released. These
warnings only end if the voltage falls below 25 V (disconnect
the apparatus and neutralise the voltage which is present on
the network to be measured) or if the yellow key is released or,
naturally, if you turn off the instrument by returning the switch to
the OFF position.
Should the voltage be greater than 600 V, the digital display
will indicate " OL ".

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3.1.2. Insulation measurement
If there is not a dangerous voltage (see § 3.1.1.), the user can
then measure the insulation by pressing the yellow key. The
high voltage is then generated between the terminals (marked
+ and -). The value of the measurement is shown on the
logarithmic scale of the bargraph and on the digital display, with
the corresponding MΩor GΩsymbol. As soon as the yellow
key is released, the instrument returns to voltage measurement
mode.
If the voltage generated may be dangerous, the symbol
is displayed.
The instrument indicates if the value measured is outside
its measurement range. If the insulation resistance is greater
than 2 GΩ, the OL symbol is displayed on the digital
measurement display.When the measurement is greater than
2 GΩ, the symbol lights up on the right-hand side of the
bargraph.
Similarly, if the insulation resistance is less than 50 kΩat 250V,
100 kΩat 500 V or 200 kΩat 1000 V, the digital measurement
display indicates “ - - - “ . When the measurement is less than
50 kΩ, only the symbol lights up on the left-hand side of the
bargraph.
Specific remark concerning the C.A 6523 and C.A 6525 :
A programmed alarm threshold can activate itself (see § 4.5).
Specific remark concerning the C.A 6525 :
The measurement can be timed (see § 4.7).
3.2. Continuity
The continuity measurements correspond to the “ 20 Ω+ “ or “
20 Ω- “ switch positions.
The instrument takes a measurement at I ≥200 mA and the "Ω"
symbol is displayed.If the threshold is active (ALARM function)
with the buzzer on, the buzzing starts very quickly (tens of
milliseconds); even before the measurement is displayed.
Between the “ 20 ΩΩ
ΩΩ
Ω+ “ position and the “ 20 ΩΩ
ΩΩ
Ω- “ position,
the direction of the current is inverted. The result of the
measurement is the mean (to be calculated by the user) of the
value displayed in the “ 20 Ω+“position and the value displayed
in the “ 20 Ω- “ position.
Continuitymeasurements shallbeperformedonidlecircuits.
The fuse protecting against external voltages is checked
when the apparatus is started up and at the end of each
continuity measurement.
The instrument indicates if the value measured is outside
its measurement range. If the resistance is greater than 20 Ω,
the OL symbol is displayed on the digital measurement display.
Specific remarks concerning the C.A 6523 and C.A 6525 :
The resistance of the measurement leads can be compensated
(see § 4.6).
A programmed threshold may trigger an alarm (see § 4.5).

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Specific remark concerning the C.A 6521 :
In continuity mode, a lower threshold of 2 Ωis constantly active.
However, the buzzer can be deactivated by pressing the yellow
key.
3.3Resistance (C.A 6523 and C.A 6525)
Resistance measurement corresponds to the 400 kΩposition
of the switch on the C.A 6523 or C.A 6525.
The Ωsymbol is displayed with the k symbol if necessary.The
measurement is indicated on the digital measurement display.
The instrument indicates if the value measured is outside
its measurement range. If the resistance is greater than
400 kΩ, the OL symbol is displayed on the digital measurement
display.
Resistance measurements shall be performed on idle
circuits.
A programmed threshold may trigger an alarm (see § 4.5).
4. SPECIAL FUNCTIONS
4.1. Start/stop
When you move the switch from the OFF position to one of the
active positions, the battery voltage is applied to the circuit.The
instrument starts up and all the display segments light up at the
same time for 1 second. All the segments then go dark except,
for 2 seconds, the , and symbols which delimit the
size of the bargraph.The bargraph indicates the battery charge
life and the digital measurement display which indicates the
charge life available (0 to 100%) for a battery voltage varying
from 6.7 to 10 V.
The instrument can be shut down at any time by moving the
switch to OFF, which cuts off the battery power supply to the
whole instrument.
.
4.2. Automatic shutdown
After5 minuteswithoutanyactivitybytheuser onthe instrument
(key press on the keyboard or on the yellow key on the remote
control probe or turn of the rotary switch), the instrument shuts
down automatically.It is then on standby.When this is the case,
to start up the instrument again, all you have to do is press one
ofthe keys,turntheswitch orpress theyellowkey onthe remote
control probe of the C.A 6523 or C.A 6525.
The automatic switch-off is inhibited during continuity
testingas longasthe measurementbeing madevaries between
a value (between 0 W and 20 W) and OL (which means that
measurement is in progress).
On the C.A 6525, in TIMER mode (see § 4.7), the five minutes
beforeautomatic shutdownonly beginatthe endofthe maximum
15-minute measurement period.

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4.2.1. Deactivation of automatic shutdown function
(C.A 6523 and C.A 6525)
Pressthe buttonwhenswitchingonthe devicevia therotating
switch.The
P
symbol isdisplayed,indicating thatthe automatic
shutdown function has been deactivated.
To reactivate the automatic shutdown function, switch the
instrument off (turn the switch to OFF) and then switch it back
on again.
4.3. Power supply autotest
Thepowersupply voltageismeasured automatically onceevery
second.Thevoltagerangeensuringcorrect operation isbetween
7V and 10 V.Depending on the result of the autotest, there are
four possible cases :
■The voltage is correct :
The symbol is not displayed on the screen.
■The remaining charge life is close to the limit for correct.
(< 7.1 V) : the symbol flashes.
■Accuratemeasurementcan nolongerbe guaranteed,change
the batteries (V ≤6.9 V) : the symbol remains lit
continuously.
■The voltage is close to interrupting operation of the clock
(< 6.7 V) : the digital display indicates BAT and then, after
5 seconds, the shutdown buzzer sounds and the automatic
shutdown function is activated.The instrument shuts down.
4.4. Buzzer
4.4.1. The different audible signals
When the symbol is displayed, the buzzer is active. It gives
out different audible signals, depending on the situation.
■Short buzz (65 ms at 2 kHz) in the following cases :
- press on a key,
- automatic shutdown,
- lead compensation taken into account,
- and after 30 s, 1 min and 10 min of insulation measurement
in TIMER mode (C.A 6525).
■Continuous buzz (at 2 kHz) in the following cases :
- when the measurement is lower than the minimum
threshold,
- when the measurement is higher than the maximum
threshold.
■Short, higher buzz (65 ms at 4 kHz) in the following case
when a deactivated key is pressed (except the yellow key).
■Repeated high buzzes (at 4 kHz)in the following case :
if the voltage measured is greater than 25 V and the user is
pressing the yellow key.

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4.4.2. Deactivation of the buzzer
■C.A 6521 :set the switch to continuity measurement (20 Ω+
or 20 Ω-) and then press the yellow key.The buzzer is then
deactivated and the symbol is no longer displayed.To reac-
tivate the buzzer, press the yellow key again or switch the
instrument off and then back on again.
■C.A 6523 and C.A 6525 : Press the ALARM button when
switching on the device via the rotating switch.The symbol
disappears from the screen.
To reactivate the buzzer, turn off the device and switch on
again.
4.5. Alarm thresholds (C.A 6523 and C.A 6525)
Each position of the switch corresponds to a high or low alarm
threshold value.In the 20 Ω+ and 20Ω- position, the thresholds
are identical and hence either one can be programmed in for
these two positions. The thresholds can be either low or high.
They can also be activated or inactivated and will be stored in
memory even after the device has been switched off.
4.5.1. Programming of the alarm thresholds
You can selectthe threshold programmingmodebya long press
on the ALARM key. The ALARM symbol is displayed and the
value of the threshold corresponding to the switch position is
indicated on the digital threshold display.
If no value was programmed previously,the display indicates
a default threshold :
> 0.25 MΩfor the MΩ- 250 V position
> 0.50 MΩfor the MΩ-500 V position
> 1.00 MΩfor the MΩ-1000 V position
< 10.00 kΩfor the 400 kΩposition
< 2.00 Ωfor the 20 Ω+ and 20 Ω- positions
At this moment, it is possible to program the threshold using the
(see § 2.3.3) and keys (see § 2.3.4). During this programming,
the instrument continue measuring.
You can quit the programming mode and record the threshold
by another long press on the ALARM key.
If the switch is activated before the second long press on
ALARM, the programming is not recorded.
If the programmed threshold is too high, it is corrected when
it is stored in the memory : the maximum value is entered. For
example, for continuity measurement, a 30.00 Ωthreshold will
be stored as 20.00 Ω(max. value for continuity).
If the threshold has been “wrongly” programmed, it is corrected
when it is stored in the memory : For example, 002 MΩwill
become 2.00 MΩ.
4.5.2. Activation/deactivation of the alarm thresholds
The threshold corresponding to the switch position can be
activated by a short press on the ALARM key.

33
The ALARM symbol, the < or > symbol, the programmed value
of the threshold and the corresponding unit are then displayed
on the digital threshold display.
The threshold can be deactivated by a second short press on
thekey.The ALARM symbol,the <or >symbol, theprogrammed
value of the threshold and the corresponding unit disappear.
4.5.3. Triggering of the alarm
If, during continuity measurement for example, a low threshold
value of say 10 Ωis activated, then the device displays
“ALARM < 10.00 Ω“.As soon as the measurement goes below
this value, a continuous audible signal will be emitted to indicate
the continuity, and all of the digital thresholds display will flash.
Similarly, if during insulation testing for example, a high
threshold of say 100 MΩis activated, the device displays
“ALARM > 100.0 MΩ”.AAs soon as the measurement exceeds
this value, a continuous audible signal will be emitted to confirm
the right insulation, and all of the digital thresholds display will
flash.
If no threshold is activated, the threshold digital display turns
itself off.
4.6 Compensation of measuring leads
(C.A 6523 and C.A 6525)
Compensation for the resistance of the measuring leads can
be accessed in continuity measurement mode (20 Ω+ or 20 Ω
- positions).
To compensate, simply short-circuit the leads and keep the
keypressed forsometime (longpress).When the measurement
has been recorded, the buzzer sounds. From this moment
onwards, the measurements displayed will be automatically
reduced by the value recorded and the
W
0
symbol will be
displayed.
To cancel the compensation, leave the leads unconnected and
press the key for some time (long press). As soon as the
instrument measures a value greater than 5 Ω, the lead
compensation is cancelled and the
W0
symbol goes out.
Turning off the device also cancels the lead compensation.
In all cases, the maximum 20 Ωcontinuity measurement is
reduced by the recorded compensation value.
Note : when you change the leads, the measurement may
become negative if the compensation is higher than the
resistance measured + the resistance of the new leads. 0.00 is
then displayed up to -0,02 Ωand the
W
0
and symbols flash
to indicate that the lead compensation is not longer suitable
and should be redone.

34
4.7. Timer (C.A 6525)
The timer function is available for insulation testing (MΩ
positions).
When you press theTIMER key, the symbol appears in front
of the digital threshold display which indicates 0:00 (timer). If
there was a programmed threshold displayed, it disappears.
An initial short press on the yellow key starts both the timer and
insulationmeasurement.You donothave tokeepthekeypressed
down.
A second press stops the timer and the measurement.The last
valueofthe timerremains displayedandthe instrumentswitches
back to voltage measurement.
To performanothertimed measurement,simply pressthe yellow
key again. The timer is then reset to zero and restarts along
with the measurement.
To quit the timer mode, simply press the TIMER key again or
switch the instrument off and then on again. The symbol is
no longer displayed.
After 30 seconds, 1minute and 10 minutes, the instrument’s
buzzer sounds. this is to allow those users who require it to
calculate the dielectric absorption rate
(= measurement after 1 min / measurement after 30 s) and the
polarization index
(= measurement after 10 min / measurement after 1 min).
Reminder : for acceptable insulation, they must be greater than
1.25 and 2, respectively.
When measuring, if a threshold is exceeded, the buzzer sounds
and display of the timer is interrupted to display the
corresponding alarm message (see § 4.5.3).
If you forget to stop the insulation test, the instrument
automatically switches back to voltage measurement after 15
minutes and the TIMER remains blocked at 15:00.
5. USE
Inorder tosuccessivelydisplaythecalibrationdate,thesoftware
version and the serial number of the apparatus, press the yellow
key when turning the switch to start the apparatus up.
To start up the machine, set the rotary switch to the type of
measurement to be performed and then connect the instrument
to the installation to be tested. The unit is displayed and the
calibre is selected automatically for the best reading.
Theinstrument canbe shut downmanuallybysetting the switch
to OFF. Otherwise, the instrument will be shut down
automatically after 5 minutes without any sign of the presence
of a user (see § 4.2).

35
5.1. Insulation testing
(see § 10.1 Examples of applications)
■Start up the instrument by setting the switch to MΩwhich
will provide the required voltage.
■Connect the lead from the“ + ”terminal to the cold point and
the lead of the “ - ” terminal or the remote control probe of
the C.A 6523 or C.A 6525 to the hot point.
■The instrument first checks that there is not a dangerous
voltage between its terminals (see § 3.1.1).
■On the C.A 6523 et C.A 6525, the user can control the dis-
play backlighting by pressing the key .
■Then press the yellow key, keeping it pressed down until the
measurement is displayed.The yellow key on the C.A 6523
and C.A 6525 remote control probe acts in exactly the same
way as the yellow key on the instrument (see § 3.1.2).
■Readoff the displayedvalue.If thedigital valuevariesgreatly
for highvalues(> 500MΩ), thenthe load ishighly capacitive.
If this is the case, read the measurement off the bar graph.
■After the measurement, let go of the yellow button and wait
a couple of seconds whilst the test mechanism discharges
(voltage < 25 V) before disconnecting the leads.
On the C.A 6523 and C.A 6525, an alarm threshold can be
activated using the ALARM key (see § 4.5).
On the C.A 6525, you can perform timed measurement using
the TIMER key (see § 4.7).
5.2. Continuity measurements
■Start up the instrument by setting the switch to 20 Ω+.
■On the C.A 6523 and C.A 6525, it is possible to compensate
for the resistance of the measurement leads (see § 4.6).
■Connect the + and - leads to the measurement points.
■On the C.A 6523 et C.A 6525, the user can control the dis-
play backlighting by pressing the key .
■Note the first value displayed (see § 3.2).
■Then set the switch to the “ 20 Ω- “ position.
■Note the second value.
■Then calculate the mean of the two values to obtain an ac-
curate result (this continuity measurement mode with a cur-
rent circulating in two different directions, 20 Ω+ et 20 Ω-, is
mainly interesting when there are self-inductive or capaci-
tive elements in the circuit to be tested).
Inductive load measurements are limited to 4 H, beyond
which the device risks being damaged.
On the C.A 6523 and C.A 6525, an alarm threshold can be
activated using the ALARM key (see § 4.5).

36
5.3. Resistancemeasurements(C.A6523andC.A6525)
■Start up the instrument by setting the switch to 400 kΩ.
■Connect the + and - leads to the measurement points.
■The user can control the backlighting as required by press-
ing the key .
■Note the resistance value displayed (see § 3.3).
On the C.A 6523 and C.A 6525, an alarm threshold can be
activated using the ALARM key (see § 4.5).
6.CHARACTERISTICS
The instrument displays a measurement every 400 ms, which
corresponds to 2.5 measurements per second for the digital
display. The bargraph is refreshed every 100 ms. The digital
measurement is smoothed, while the bargraph always indicates
the instantaneous measurement.
6.1. Reference conditions
Influencequantities Referenceconditions
Temperature 23 °C ± 3 K
Relativehumidity 45 to 55 % RH
Supply voltage 8 V ± 0.2 V
Capacity in parallel on resistance nil
Electrical field nil
Magneticfield < 40 A/m
6.2. Characteristics per function
6.2.1. Voltage detection
Thisvoltagedetectionis automaticbefore andaftertheinsulation
measurements have been performed.
Indicating range: 0...600 V AC/DC
6.2.2. Insulation
Measurement range :
■C.A 6521 : at 250 V 50 kΩto 2 GΩ
at 500 V 100 kΩto 2 GΩ
■C.A 6523 : at 500 V 100 kΩto 2 GΩ
at 1000 V 200 kΩto 2 GΩ
■C.A 6525 : at 250 V 50 kΩto 2 GΩ
at 500 V 100 kΩto 2 GΩ
at 1000 V 200 kΩto 2 GΩ

37
Analoguecalibre 50kΩ...2 GΩ
Resolution 8 segments per 10-unit interval
Accuracy 5 % L ± 1 segment
Digital 0.01 to 0.20 to 40.0 to 400 MΩ
calibres 0.19 MΩ39.99 MΩ399.9 MΩto 2 GΩ
Resolution 10 kΩ100 kΩ1 MΩ
Accuracy 3%R± 5ct 3%R ± 2ct
Test voltage 250 V 500 V 1000 V
Voltage at < 300 V < 600 V < 1200 V
open circuit
Test current ≥1 mA ≥1 mA ≥1 mA
for R ≤250 kΩfor R ≤500 kΩfor R ≤1 MΩ
Short-circuit ≤3 mA
current
Once the yellow key has been released, the residual voltage
present on the terminals is discharged via the measuring cords
through the apparatus at the speed of 1.5 s/µF and in an
impedance of 300 Ω.
■Average charging time depending on the capacity in
parallel on the resistance to be measured.
500V 1000V
1 MΩ3 s 3 s 1 µF
3 s 6 s 5 µF
100 MΩ6 s 6 s 1 µF
20 s 20 s 5 µF
6.2.3. Continuity
Measurement range : 0 to 20 Ω
Calibre 0.00...19.90Ω
Resolution 10 mΩ
Accuracy ± 3% L ± 1 pt
Measuring current ≥200 mA
Voltage at open circuit 7V ≤Vopen ≤9 V
6.2.4. Resistance (C.A 6523 and C.A 6525)
Measurement range : 0 to 400 kΩ
Calibres 0.0...399.9Ω400..3999Ω4.00..39.99kΩ40.0..399.9kΩ
auto.
Resolution 0.1 Ω1 Ω10 Ω100 Ω
Accuracy ±3%L±5 pt ± 3% L ± 1 pt
Test 55 or 550 µA according to the measurement
current
Voltage at 7 V ≤V open ≤9 V
opencircuit

38
6.2.5. Timer (C.A 6525)
Measurement range : 0 to 15 min
Calibre 0:00 to 15:00
Resolution1second
Accuracy 0.5 % L
6.3. Power supply
The instrument is powered by 6 x 1.5V alkaline batteries, type LR6.
Measurement Average* Average
consumption chargelife
Voltmeter 25 mA 57,6005-secondmeasurements
Resistance 50 mA 28,0005-secondmeasurements
Insulation 160 mA 7,2005-secondmeasurements
250V (R = 250 kΩ)
Insulation 200 mA 3,8005-secondmeasurements
500V (R = 500 kΩ)
Insulation 350 mA 1,4405-secondmeasurements
1000V (R = 1000 kΩ)
Continuity 230 mA 3,3005-secondmeasurements
* Add approximately 45 mA when the backlighting is on.
6.4. Climatic conditions
0
10
20
30
40
50
60
70
80
90
-50 -40 -30 -20 -10 0 10 20 30 40 50 60 70 80 90
Storage without battery
Humidity in % of HR (non-condensing atmosphere)
Use Reference
Temperature in °C
6.5. Variations in nominal field of use
Influence Range Measurement
quantities for variations
use Typical Maximum
Temperature -10 to +55°C (1% R ±1 ct)/10°C (2%R ±2 ct)/ 10°C
Relative 20 to 80% RH 2% R ± 2 ct 3% R ± 2 ct
humidity
Supply 6.9 to 10V (1% R ± 1 ct)/V (2 R ± 2 ct)/V
voltage
Capacity 0 to 5 µF
in parallel atthenominal Negligible 1% ±1 ct
on the resistance current

39
6.6. Limits
The three apparatuses are protected on all the nominal ranges
against a voltage of 720V AC/DC applied continuously between
the two terminals.
The C.A. 6523 and C.A. 6525 models are protected on the MΩ
nominal range for 1,200 V AC and DC for 10 seconds.
6.7. Construction specifications
■Dimensions of the display : 73 mm x 54.3 mm
■Overall dimensions of the unit (L x l x h) : 211 x 108 x 60 mm
■Weight : approx. 830 g
■Materials :
- Polycarbonate casing
- Crystal polycarbonate screen
- Elastomer external mouldings
- Silicon keyboard.
■Stand :
Enables the instrument to be tilted at 30°. It clips onto the
bottom of the casing when not in use.
6.8. Compliance with international norms
■Electrical safety per IEC 1010-1 + A2 (Ed. 95), IEC 61557
(Ed. 97) and DIN EN 61557
■Dual insulation :
■Pollution degree : 2
■Installation category : II
■Rated voltage : 300 V
6.8.1. Electromagnetic compatibility : EC compliance
■Emission : NF EN 55 081-1 (Ed. 92)
■Immunity : NF EN 55 082-2 (Ed. 98)
6.8.2. Mechanical protection
IP54 according to NF EN 60529 (Ed. 92)
IK04 according to NF EN 50102 (Ed. 95)
7. MAINTENANCE
For maintenance, use only specified spare parts. The
manufacturer will not be held responsible for any accident
occuring following a repair done other than by its After Sales
Service or approved repairers.
7.1. Upkeep
7.1.1. Replacing the batteries
Before performing any measurements, make sure that the
symbol does not appear on the display during the start-
up phase. If it does appear, you must change all the batteries,
taking all the necessary precautions when you open the
instrument.

40
Check that none of the terminals is connected and that the
switch is set to OFF before opening the battery
compartment.
The hatch is located on the back of the unit. It can be opened
and closed using a coin or a large screwdriver (1/4-turn captive
screw).To avoid errors, the symbol on the
power-supply board shows the direction in which the 2 x 3 LR6
1.5 V batteries should be mounted. Make sure that you put the
hatch back properly and close it after changing the batteries.
7.1.2. Replacing the fuse
If “FUS” appears on the digital measurement display during the
start-up phase or when measuring continuity, you must change
the fuse, taking all the necessary precautions when opening
the instrument.
Check that none of the terminals is connected and that the
switch is set to OFF before opening the battery hatch on
the back of the instrument.
It can be opened and closed using a coin or a large screwdriver
(1/4-turn captive screw). The fuse is placed on a fuse carrier
welded to the power-supply board.
To avoid any errors, the text“F-0.63 A”is written next to the fuse
carrier. Make sure that you replace the faulty fuse with fuse of
the same rating and type and then replace and close the hatch.
Exact type of fuse : FF 0.63 A - 660 V - 6.3 x 32 mm - 30 kA
(marked on the battery compartment label).
7.1.3. Cleaning
The instrument must be disconnected from any source of
electricity.
Use a soft cloth slightly moistened with soapy water.Rinse with
a wet cloth and dry quickly with a dry cloth or pulsated air. Do
not use alcohol, solvents or hydrocarbons.
7.1.4. Storage
If the instrument remains unused for an extended period (more
than two months), remove the batteries and store them
separately.
7.1.5. Calibration
It is essential that all measuring instruments are regularly
calibrated.
For checking and calibration of your instrument, please contact
our accredited laboratories (list on request) or the Chauvin
Arnoux subsidiary or Agent in your country.
7.2. Maintenance
Repairs under or out of guarantee:please return the product to
your distributor